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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        function uniqe(arr){
            let newArr = [];
            for(let i=0;i<arr.length;i++){
                if(newArr.indexOf(arr[i])===-1){
                    newArr.push(arr[i])
                }
            }
            return newArr
        }
        let arr1 = [11,13,12,11,12,42,33,33]
         let arr2 = uniqe(arr1);
         console.log(arr2);
    </script>
</body>
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